1. Technical Field
The present invention relates to a printing method and to a printing device.
2. Related Art
In the marking industry, where laser marking predominates, there has recently been a desire for an alternative technique for IC thinning, based on damage, poor visibility, and other problems. One such alternative technique for laser marking is a technique for coating a recording medium using an ink jet method for dropletizing and discharging a functional liquid, and printing predetermined information on the recording information by solidifying the coated functional liquid. Japanese Laid-Open Patent Publication 2003-80687 discloses a printing device for using an IC chip as a recording medium and printing a serial number, manufacturing company, or other predetermined information on the IC chip.
As an application of such marking, attention has also turned to ink jet devices for using an ultraviolet-curable ink, which is curable by being irradiated with ultraviolet rays, to record through an ink jet method. Ultraviolet-curable inks, in curing extremely slowly until irradiated with ultraviolet rays, and curing rapidly once irradiated with ultraviolet rays, have preferable characteristics as printing inks. Another advantage is that the environmental impact is small, because no solvent is volatilized during the curing.
Ultraviolet-curable inks, depending on the composition of the vehicle, are also readily bonded to various different recording media. Ultraviolet-curable inks are also chemically safe, highly adherable, highly resistant to chemical agents, highly weather-resistant, and highly friction-resistant, and are also able to withstand an outdoor environment, among other excellent characteristics. For this reason, in addition to paper, resin film, metal foil, and other thin sheet-shaped recording media, an image can be formed on labeling surfaces, textile products, and other surfaces having a certain degree of three-dimensional shape.
In the marking of IC chips, favorable visibility of characters as well as scratch resistance and solvent resistance are desirable. In, for example, Japanese Laid-Open Patent Publication 11-145314, an IC chip to be marked is irradiated with activation light, which enhances wettability, with the purpose of enhancing scratch resistance and solvent resistance.